Centrifugal Casting of Large Ti-6Al-4V Structural Components supported by Process Modelling

The usage of large structural Ti components in airframe and spacecraft can lead to significant weight saving and thus reduce
fuel consumption and emission. From a cost point of view such intrinsic components can be manufactured by a centrifugal
investment casting process. The large size of the castings (order of size 1-2 m), its thin-walled geometrical features (lower
limit 5 mm) and the limited superheat (40°C imposed by the clean-melting process) requires the application of centrifugal
casting to obtain a complete mold filling. Casting modelling capabilities were developed to predict centrifugal mold filling,
solidification, porosity formation, stress and deformation to support the casting process design. The article shows in detail
the features of the casting modelling (material properties, interface heat coefficient, boundary conditions), how the
modelling results compare with the real casting and what measures were actually taken to ensure and improve the quality of
the casting parts. This work was achieved in the frame of the FP7project COLTS with European and Chinese partners
(http://www.colts-project.eu/).